About Step3
Step3 is a cutting-edge multimodal reasoning model—built on a Mixture-of-Experts architecture with 321B total parameters and 38B active. It is designed end-to-end to minimize decoding costs while delivering top-tier performance in vision–language reasoning. Through the co-design of Multi-Matrix Factorization Attention (MFA) and Attention-FFN Disaggregation (AFD), Step3 maintains exceptional efficiency across both flagship and low-end accelerators.
Specifications
- Provider
- Stepfun ai
- Context Length
- 65,536 tokens
- Input Types
- image, text
- Output Types
- text
- Category
- Other
- Added
- 8/28/2025